Furnace



Oct. 5 192s. l,601,909

W. C. DRAKE ET AL FURNACE Filed June 25, 1920 2y gets-Sheet 1 8(MIBTPMArron/VH8) Oct. 5, 1926.- 1,601,909

' W. C. DRAKE ET AL FURNACE Filed June 25, 1920 2 Sheets-Sheet 2 wInventorS (11mm Q.

Attys,

Patented a. 5, 1926'.-

UNITED STATES PATENT OFFICE.

wamn c. Danica am). manner is. PBIEBE, or mwoon, NEW roux.

- FURNACE.

Application filed June 85, 1920. Serial No. 881,604.

This invention relates to furnaces; and

-to the combustion chamber, for example, di-

rectly into the fuel bed. It has already been known to supplyainunderressure 1n this manner for the purposes 0 protecting the walls againstexcessive heat, and promoting combustion, and 'minimizing the formatlonof clinkers and the adherence thereof to the walls. The main objectofthe present invention is to provide a furnace or furnace wall of thegeneral character and for the purposes mentioned but of improvedefficiency, durability, and convenience. The

. further objects and advantages of the invention will be explained inthe hereinafter following description of one or more em-' bodiments, orwill be apparent to those skilled in the art.

To the accomplishment of such objects and advantages the presentinvention consists in the novel furnace, furnace wall, wall element orbrick, and the features of conj structlon, arrangement, combinatlon, and

detail herein illustrated and described.

In, the accompanying drawings forming a part hereof, Figure 1 may beconsidered a vertical lon 'tudinal section taken substantially on t eline 11 of Fi ..2, 'and showing a furnace of the under eed type withinclinedgrate, and embodying the features of the present invention.

Figure 2 is a plan view taken partly in horizontal section on the line22 of Fig. 1. Figure 3 is a perspective view of one form of blockadapted to be em loyed in building the perforated portion 0 the wallshown in Figs. 1 and 2; and Figure .4 is a planview thereof. Figure 5shows in perspective a second or modified form of block adapted to givea somewhat different but equivalent form of wall.

Figure 6 shows in perspective a third form or modification of furnacewall block; and Figure 7 is a horizontal section thereof. Figure 8 showsin perspective a pair of blocks of a still different form. blFigure 9shows a still different form of Figure 10in perspective shows a portion.

ver actuated shaft 24'? Figure 11 indicates a modification in the modeof' bondin or looking together two successive tiers 0 blocks.

Figure 12 in perspective shows one of the overlyin bricks or cover tilesof Figs. 1 and 10 ut inverted. The invention may be applied to furnacesof various types, for example, the underfeed type, which is shown in Fis. 1 and 2. In these figures is indicated a having openings 21 leadingdownwardly into a series of ram boxes or casings 22,

within which reciprocating rams 22 operated by connecting rods 23extending from a crank shaft 24. The crank shaft is shown as driven byworm gearing 24 from a pow- Connections 25 are shown for agitatingcertain portions of the grate...

The coal thrust inwardly by the rams, flows upwardly so as to overliethe furnace grate, consisting of a series of tuyere boxes 27 and betweenthem a series of retorts 28. This entire structure is shown as inclinedtoward the furnace rear in a well known manner. At the foot of theinclined grate is a grate section 29, and to the rear of that a dumpinggrate 30 adapted to be dropped and lifted periodically.

. The eneral outline of the fuel bed lying upon t e grate 272829--30,may be as indicated y the broken line 31 in" Fig. 1.

The furnace may be fed by forced draught, and for this purpose a mainair duct 32 is shown leadin from a blower or other source of air un orpressure, The pipe 33 is shown leading from the air duct 32 to thetuyere boxes, whereby airfor combustion is forced into the under side ofthe fuel bed in a well known manner. Leading also from the main air duct32 are shown pipes 34 which extend to the air passages in the walls aswill be described."

The furnace front wall 36, side walls 37, and bridge wall 38 afiordacombustion chamber 39 above which may be a boiler 40 of any type.

Each of the .four walls, or one or more of them, at the point where theair is to be admitted or injected, is recessed at its inner side,forming a cavity 42 within which are mounted special furnace wallelements adapted to afford apertures or perforations for conducting theair to the combustion chamber. Between the perforated portion of eachWall and-the outer or body portion el hopper v thereof, is formed aspace 43 connecting with the air pipes 34 already mentioned andconducting the air supply to the inwardly directed perforations of thewall. A passage 44 is provided by which the air is also conducted to thespace 43 within the rear or bridge wall of the furnace.

The perforated portion of each wall is shown as built up of a pluralityof blocks. bricks, or tiles, arranged to a give an inner surface whichis'flush with the general surface of the wall. These special blocks maybe of different forms, as will be described, and are such as to givecertain advantageous features and result, as will be made clear. Such ablock 45 is shown in Figs. 3 and 4, and in the upper or righthandportion of Fig. 1. A different form of block 45 is shown in Fig. 5, andat the intermediate portion of the side wall in Fig. 1. Another form ofblock 45 is shown in Figs. 6 and 7 and in the lower or left portion ofFig. 1. In each cam it will be noticed that the block is ofrhomboida'l-shape so that'the several blocks, where they lie contiguousto each other, meet so that they fit snugly together, affording a solidand durable wall. It will also be observed that the supporting partsbelow the perforated wall, and the wall bricks or tiles above it, areshaped to conform to the general slanted character. of the perforatedarea and the fuel bed.

It is an important and valuable feature of the present invention thatthe inwardly directed air perforations are formed at a substantialincline. Thus, in the side walls, as best seen in Fig. 2, the aperturesare directed inwardly and at a forward slant. This not merely gives amotion to the air in the general direction of the advance of the fuelbed but tends to protect the perforated wall against injury and cloggingby the advancing fuel. A better co-operation occurs withthis novelarrangement. On the front wall as indicated in Fig. 2, the apertures arepreferably directed at a slant toward the axis or generally toward thecenterof the furnace which may in certain circumstances bring about asubstantial benefit in the operation of the furnace.

The detail structure of the blocks 45 is best seen in Figs. 3 and 4. Thewall aper-' tures for the supply of air to the fuel bed are not formedby perforations through the body of each block but are formed by groovesor channels 46 at the upright edges of each block. These air grooves 46are shown as tapered so as to give a greater force and the effect of anozzle at the orifice. Three grooves 46 are shown at each side edge ofeach block, and these may be semi-circular in cross-section and arrangedto register with the corresponding grooves of the adacent block, so asto afford circular wall apertures.

each block is shown as formed withone ormore shallow depressions orrecesses 47 at its inner face. Each of the air orifices is then made todischarge at the narrow face recess or depression thus formed,'and,being inset and pro.tected, the flow of air is maintained with greateruniformity.

Each block 45 is further provided with upper and under grooves 48 forthe purpose of bonding or interlocking the furnace wall. elements, aswill be described.

In the furnace block 45*, shown in Figs. 1 and 5, the features aresimilar to the block 45 but the three separate grooves 46 are replacedby a single wide groove 49, which is of uniform height but in width istapered or converging from rear to front as shown.

The block shown in Figs. 1, 6 and 7, differs from the preceding in thatthe air perforations are formed by tapering interior holes 50 throughthe body of the block.- Three such apertures are shown, and theirorifices discharge through a shallow depression 51 at the face of theblock.

With each of the three formsof block described, the apertures aredirected horizontally into the combustion chamber, and the blocks arefitted together and arranged so as to afford the air passage 43 behindthem; and in Fig. 2 are shown special terminal blocks 52 at the end ofeach tier, tio facilitate fitting of the blocks into the furnace walls.

A somewhat difierent form of block is shown in Fig. 8. Two similaradjacent blocks are here shown somewhat separated. They are constructedto afford the tapering air perforations without the employment either ofthe holes 50 through the body of the block, as in Figs. 6 and 7, orregistering grooves, as in Figs. 3 and 4. The left side edge ofeachblock is shown provided with a tapered recess 53, and theco-operating face of the next block is withoutrecesses and may beprovided with a rib 54 acting to divide the recess 53 into two separateair apertures.

With the structures previously described, the air apertures are directedhorizontally into the fuel bed or combustion chamber; but in some casesit is advantageous to direct the incoming air at a downward slant astending to give better action and more efficient protection to thewalls. Such a structure is indicated in Fig. 9, where the apertures areslanted both downwardly and toward the furnace rear, the blockbeingotherwise similar to those already described.

Jier of the special blocks is 1 below the same. For this purpose theblocks are specially constructed, for example, bythe grooves 48, beforementioned, adapted to cooperate with looking members to give interenagement.

ig. 10 shows a solid side wall or bed casting 55 which underlies theentire system of special furnace blocks. This is shaped to accommodate arefractory facing or brick 56 for the protection of the metal, and theupper rear portion of the casting 55 isv formed with a longitudinalbonding ortion or rib 57 A tier of assembled urnace blocks is" shown asresting on the elements and 56, with the grooves 48 of the blocksengaging the rib 57 of the supporting bed plate. A second tier of blocks45 is indicated above'the first tier in this figure, and the two areshown united by a bonding 'or looking rod 59 which maybe drawn out fromthe front to permit disengagement of rately in inverted position in Fig.12. Each of these has a beveled under side 63, and a rib 64 projectingdownwardly therefrom at t e top sides of the blocks.

It will thus be seen that we have described a furnace and one or moreforms of furnace wall and wall blocks embodying the.

principles and attaining the advantages of the present inventlon. Sincevarious matadapted to engage in the locking grooves 48.

ters of combination, arrangement, design and detail may be modifiedwithout departing from the principles involved, it is not intended tolimit the present invention to such. matters, except so far as specifiedin the appended claims.

What is claimed is:

l A furnace wall comprising inclined tiers of blocks constructed toafiord'air aper- --tures to the fuel bed, an inclined support for saidblocks, and horizontal elements overlying and interengaging the topmosttier of blocks, and means for supplying forced draft to such inlets.

2. A furnace wall as in claim 1 and wherein the lowermost tier of blocksengages the support by a tongue and groove engagement.

3.. A furnacewall as in claim 1 and wherein the block is groovedbothabove and below to engage bonding means. 4. A furnace wall as inclaim- 1 and where-' in the horizontal overlying elements or bricks areconstructed for bonding-engagement with-the topmost tier of bricks.

5. In an automatic underfeed furnace the combination of means forsupporting and progressively advancing the fuel bed at a -substantialincline from the fuel entrance downwardly toward the fuel discharge,furnace walls enclosing the combustion chamber, and each side wallarranged to confine laterallythe inclined fuel bedat one side.

and comprising in its structure an inclined tier or tiers of aperturedrefractory blocks "of WARREN o. DRAKE. ERNEST B. PRIEBE.

